Upon arrival inspected unit and found furnace was overheating on E09, no specific causes for overheating aside from the gas pressure at 2.0 on low 3.7 high set pressures down to 1.5 low and 3.2 low and adjust blower speeds on system to assist with allowing heat to escape the burner compartment. Previous invoice disappeared, upon last visit found blower limit was unplugged at the housing inside unit from different company replacing the motor. Test ran system and heat was operational after adjustments were made but system had been still overheating.